Recently I came down with my first case of poison ivy. And it's a doozy. A trip to the doctor last Monday has me on medication that's clearing it up quickly, though. I'll be happy to see it go away completely! Since this was my first case of the scratchy stuff, I did a little research online and discovered that a lot of the things I thought were facts about poison ivy turn out to be nothing but myths.

• Scratching will cause the rash to spread. Technically, this isn't true. The rash is caused by contact with urushiol oil from the poison ivy plant. If your skin still has traces of the oil and you scratch, you could transfer the oil to another part of your body. But, once the oil is gone, scratching will not spread the rash. However, take it from my personal experience, you don't want to scratch. I'm on a heavy-duty antibiotic to clear up the infection I have as a result of scratching.
  
• Poison ivy is contagious. Again, only contact with urushiol oil will cause the reaction. The rash itself is not contagious.
  
• Once allergic, always allergic to poison ivy. Not necessarily. Your sensitivity can change over time.

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Have you ever had an itch so bad that you felt like sitting for hours just to scratch? It's almost compulsive, but there's a deliberate connection between the brain, skin, and that need to fix an itch. In fact, scientists say even fish scratch themselves (I'll just have to take their word for it).

So what makes it feel so good? They used MRI machines to test 13 people as they scratched their legs, even without needing to. Researchers discovered that an itch doesn't even have to be present for a scratch to feel good. The brain pepped up where pleasure resides and at the same time suppressed areas of pain sensation.

Not only that, but areas regarding memory were also affected. This sends pleasure signals through the spinal cord to tell our brain "Keep scratching!" It is also the same reason that compels us to rub our stubbed toe or hurt head after bumping into something. Just imagine pain signals and pleasure signals trying to crowd into the brain at the same time. This traffic jam effect blocks out some of the sensations you wouldn't want to feel! Check out more here if you're curious about this mechanism.

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